The present invention relates to a packaging tube, more precisely a tube of the laminate tube type. The invention relates also to a method and a device for manufacturing of the actual tube.
The term laminate tube means a tube manufactured from a laminate comprising metal foil, usually aluminium foil. Laminate tubes are well known. As time has passed by laminate materials as well as the manufacturing technique have been developed.
The market has shown a very high degree of acceptance and people within the art have realized that the laminate technique offers an alternative to metal tubes and that such alternative is an interesting one for several reasons, not at least from a cost point of view when packaging products requiring sofisticated barrier properties of the packaging tube.
A frequently occuring problem, has to do with the provision of handling characteristics which would be acceptable.
The consumer wants to roll up the tube as it is being emptied, and he/she prefers a "dead" material in such cases, i.e. a material without a tendency of returning or without "a mechanical memory". The term used within the actual technical field is a material having pronounced dead-fold characteristics. The term dead-fold falls under a broader term called "resilience" and frequently used when defining the overall characteristics of a metal foil containing laminate.
Briefly the problem may be identified by recognizing the fact that a laminate tube is more like an all-plastics tube than a metal tube (for instance lead or zinc tube), unless specific measures are taken.
The return tendency the laminate tube has, without such measures, for instance means that the contents of the tube will be exposed to a large volume of air when the tube returns to its original shape although the contents of the tube has decreased drastically.